Heating apparatus



S E L a P m HEATING APPARATUS Filed Deo. 25-i TTORNE Y Patented Oct. 26, 1948 UNITED STATES .PATENT oFFicE HEATING APPARATUS David D. Peebles, Hillsborough, Calif., assignor to Golden State Company, Ltd., San Francisco, Calif., a corporation of Delaware -i Application December 23, 1944, .Serial No. 569,551

.pose because it is diiilcult to avoid overheating or burning, and it is difilcult to prevent incrustation or building up of solid material upon the walls oi the heat exchange tubes.

In place of tubular heaters it has been proposed to employ heaters of the type in which steam is directly introduced into the liquid material. While such equipment avoids incrustation, it has been found that simple injection of the steam into a body of liquid tends to cause localized overheating with resulting burning of the material.

It is an object of the present invention to provide an improved apparatus and method ior heating lacteal materials and like food products. which will utilizedrect contact of steam with the liquid material, but which will avoid objectionable burning.

' A further object of the invention is to provide an apparatus and method of the above character enabling accurate control over the time period of heat treatment, and without undesired retention or carry back of a portion oi' the treated material.

Further objects of the. invention will appear from the following description in which the preferred embodiment has been set forth in detail in conjunction with the accompanying drawing.

Referring to the drawing- Figure 1 is a side elevational view illustrating l diagrammatically apparatus incorporating the 3 Claims. (Ci. 261-79) an inner treatment chamber I I. The outlet from the heater, as will be presently explained, connects with thetiming or retention tank I2.

The heater I is circularly contoured and consists of a top wall I3. provided with the axial outlet Il. and an annular peripheral wall I5. Bottom wall I8 is formed by a removable plate. Preferably the heater is disposed horizontally, a1- though in certain instances it may be disposed vertically and connected to tank I2 by an elbow.

For the introduction of liquid and steam into the heater I0, a plurality oi' pipes I1, I8, I9 and connect tangentially through the peripheral wall I5. The number of these .pipes may vary according to requirements. In this instance pipes Il and I9 serve to introduce liquid, while pipes i8 and 20 are for introduction of steam. A special orifice means is provided for communication between these pipes and inner chamber Ii, whereby the introduction is distributed over substantially the entire length of the distance between walls I3 and I6. In the constructionillustrated in Figure 4 pipe 20 for example connects with an orifice 22 which is simply a round hole bored tangentially through the wall I5. A metal plate |23 is fixed across the outlet of opening 22, whereby communication with the interior of the chamber I I is' confined to a narrow slit 24 which communicates tangentially with chamber II. Orice means of this type can be used for both introduction of liquid and steam, but is particularly desirable for introduction of steam as will be presently explained.

As illustrated diagrammatically in Figure 2 pipes IB and 2i) are shown connected to the common steam supply pipe 25. Pipes I1 and I9 are connected to the common liquidsupply pipe 26. A' suitable pump 21 serves to supply the liquid to pipe 26, and to enable adjustment of pressure and flow rate. this pump can be provided With a, valve controlled by-pass line 28.

'I'he size of the timing or retention tank I2 depen-ds upon the time period of retention desired. Where the period of heat treatment is to be relatively short, this tank can be omitted in entirety, or one can depend upon the prolonged heat treatment occasioned by the piping connected to the outlet I4 of the heater. trated is cylindrical and disposed in an upright position. It has a lower conical shaped portion 3l for connection with the outlet Iii. -It has an upper conical shaped port-ion 32 whichl connects to the delivery pipe 3'3, which for example may lead' to vacuum. evaporating equipment. To facilitate pressure .and temperature control pres- The retention tank illus-I sure gauges Il and SI can be provided, discharge pipe 3l can be provided with throttling valve Il.

and .thermometers or like temperature measuring devices 38 and 39 can be provided in connection with the lower and upper ends of .tank I2 in order to, check the temperatures of the liquid material at the beginning and at the end of the retention period. y

Operation of the apparatus described, and carrying out the present method, can now be explained as follows: Pump 2l is adjusted to deliver the liquid material to be treated to the heater HI at .the desired now'rate and pressure. and the retention tank i2 are maintained completely filled with liquid. and the dow rate is maintained constant. Liquid and steam are continuously injected into the periphery of the heating chamber Il and because of the relatively narrow elongated orifices 24. the steam actually enters the chamber Il as a sheet whereby it contacts a relatively large surface area of the liquid material.

Tangential introduction of liquid and steamv The heater 175 to 300 F. or even higher. It should be understood .that this temperature range is specified by way of example rather than limitation. After being heated to the desired elevated temperature the liquid material remains in the chamber Ii for only a short interval of time, after which it passes into the retention tank l2 and gradually progresses upwardly'through this tank to the discharge pipe 33. Thus the heat treatment can be prolonged for a predetermined period of time, after which .the material can be abruptly cooled, as for example by permitting it to expand in a partial vacuum.

Because of the manner in which steam is introduced and contacted with the liquid, detrimental localized burning of the material-is prevented. In addition there is no tendency for the equipment to mix back or retain portions of .the liquid material for an undue period of time beyond the desired time of retention. This is because the material is positively and progressively transferred through the heater I I and from this heater through the retention tank.v Once liquid has been contacted with the inil'owing steam it is not again contacted thereafter, but is immediately caused to tloW inwardly toward the outlet I4. The dismensioning of chamber il contributes to this result in that the height of the chamber is relatively small and preferably -a minor fraction of its diameter".

Iclaim:

1. Apparatus for heating a liquid by direct contact with steam. which comprises, a casing providing a circular peripheral wall and end walls .forming an internal circular chamber, the length of said chamber measured in the direction of its axis being a minor fraction of the diameter of said chamber, said peripheral wall having a plurality of apertures extending therethrough and spaced circumferentially of said wall. each of said apertures extending substantially the length of said peripheral wail and being directed in the same circumferential direction .tangential to the inner face of said peripheral wall, said apparatus having a liquid conduit connected to one of said apertures to deliver liquid into said chamber tangentially of said peripheral wall. one of said end walls having a centrally disposed outlet therein so .that said liquid spirals inwardly in said chamber and discharges through said outlet, said apparatus having a steam conduit connected to another of said apertures to deliver steam into said chamber ltangentially of said peripheral wall into contact with the outer peripheral surface of the spiral of liquid in said chamber so as to uniformly and rapidly heat said liquid.

2. Apparatus foi-'heating a liquid by direct contact with steam, which comprises. a casing providing a circular peripheral wall and end walls forming an internal circular chamber. the length of said chambers measured in the direction of its axis being a minor fraction of the diameter of said chamber, said peripheral wall having a plurality of apertures extending therethrough and spaced circumferentially of said wall, each of said apertures extending substantially said length of the peripheral wall and being directed in the same circumferential direction tangential to the inner face of said peripheral Wall, said apparatus having a liquid conduit connected .to one of said apertures to deliver liquid into said chamber tangentially of said peripheral wall, one of said end w-alls having a centrally disposed outlet therein so that said liquid spirals inwardly in said chamber and discharges through said outlet, said apparatus having a steam conduit connected to another of said' apertures to deliver steam into said chamber tangentially of said peripheral wall and parallel to the outer peripheral surface of the spiral of liquid in said chamber, said orifices being in the form of narrow slits having their major dimension parallel tothe axis of said chamber so as to cause said steam .to uniformly and rapidly heat said liquid.

A3. Apparatus for heating a liquid by direct con- -tact with steam, which comprises, a casing providing a. circular peripheral wall -and end walls forming an internal circular chamber having a vertical axis, the length of said chamber measured in the direction of its axis being a minorl fraction of the diameter of said chamber, said peripheral wall having a plurality of apertures extending therethrough and spaced circumferentially of said wall, each of said apertures extending substantially the length of said peripheral wall and being directed in the same circumferential direction tangential to the inner face of said peripheral wall, said apparatus having a liquid conduit connected to one of said apertures to deliver liquid into said'chamber tangentially of said peripheral wall, the upper one of said end walls having a centrally disposed outlet therein so .that said liquid spirals inwardly in said chamber and discharges through said outlet, said apparatus having a steam conduit connected to another of said apertures to deliver Vsteam into said chamber tangentialw of said peripheral-wall into contact with the outer peripheral surface of the spiral lof liquid in said chamber so as to uniformly and rapidly heat said liquid, and a vertically extending retention tank having a downwardly converging conical shaped portion at its lower end connected to said centrally disposed outlet so that the heated liquid spirals upwardly in said retention tank.

DAVID D. PEEBLES.

(References on following page) 5 REFERENCES 0mm Nggew The following references are 'of record in the 2:23519@ .le of this patent: 2.353.912

UNITED STATES PATENTS 5 Number Name Date Number 1,879,532 Stout sept- 27, 1932 403,080

. 6v Name` Dite Mathieu Feb. 18, 1936 Kleinschmidt Mar. 25, 1941 Lindsey July 18. 1944 FOREIGN PATENTS Country Date Great Brita/1n 

